Ellis D. Tripp writes "Researchers have developed a technique for determining what illicit drugs people might be consuming in a given area, by testing a sample from the local sewage treatment plant. As little as a teaspoonful of untreated wastewater can reveal drug use patterns in a given community. From the article:
"one fairly affluent community scored low for illicit drugs except for cocaine. Cocaine and ecstasy tended to peak on weekends and drop on weekdays, she said, while methamphetamine and prescription drugs were steady throughout the week."
Obviously, any drugs found can't be tied to any specific user, but how much longer until the drug warriors want to deploy automatic sampling units farther upstream of the sewage treatment plant, sampling sewage output from selected neighborhoods, blocks, or even individual houses?